1. Field of the Invention
The present invention relates to a mineral wool plant substrate, more in particular to a mineral wool plant substrate comprising a foreign material or materials in order to improve the properties of the mineral wool substrate to realize Crop Protection and/or improve plant performance in relation to additions (such as nutrients, pesticides, water and the like) as applied by growers during a cropping cycle.
2. Description of the Related Art
Mineral wool plant substrates for plant growth are well-known in the art and consist of a coherent matrix of mineral wool. This coherent matrix is formed by collecting a layer of mineral wool fibres provided with a curable binder, so that after curing the mineral wool fibres are substantially not displaceable relative to one another. If required for fast uptake of water this coherent matrix of mineral wool may be provided with a wetting agent.
Under mineral wool is to be understood glass wool, stone wool, rock wool, man made vitrous fibres, slag wool, and/or mixtures thereof.
The fibres may have an average diameter varying in between 1–10 μm. For rock wool the fibre diameter is on average about 4 μm.
The density of the coherent matrix of mineral wool may be between 10–200 kg/m3, in general in the range of 40–80 kg/m3.
Such a coherent matrix of mineral wool has a form retaining property, which is inherent due to the inorganic starting materials used. Furthermore, the water retaining capacity of these mineral wool plant substrates is very well controllable and predictable.
A problem is that growers, utilizing such mineral wool plant substrates may inadvertently stress and even damage plants by overdosing or underdosing the mineral wool substrates with additions, such as nutrient solutions, when considering plant requirements at a certain time and growth stage.